<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        body{
            margin: 0;
        }
        .pg-header{
            height:48px;
            background-color: #2459a2;
            color:white;
        }
        .pg-content{
            background-color: green;
            height: 800px;
            color: white;
        }
        .pg-footer{
            background-color: red;
            height: 48px;
            color: white;
        }
    </style>
</head>
<body>
    <div class="pg-header">
        <div style="width:980px;margin:0 auto;border:1px;border-color:red;">
            头部
        </div>
    </div>
    <div class="pg-content">内容</div>
    <div class="pg-footer">尾部</div>
</body>
</html>